It is well known that toothbrushing on a regular basis is necessary for maintenance of a condition of effective oral hygiene. Various types of toothbrushes have been employed for many years to accomplish effective cleaning of the teeth. In recent years it has been determined that effective oral hygiene can be accomplished simply and efficiently through the use of a mechanized toothbrush system whereby bristles of a brush or tufts of bristles are rapidly moved by a suitable power source which may conveniently take the form of a water powered turbine as evidenced by U.S. Pat. No. 1,108,475 and 3,605,154 or may conveniently take the form of an electrically driven mechanism as taught by U.S. Pat. Nos. 2,140,307; 2,215,031; and 4,156,620. Gear mechanisms have also been widely used in powered toothbrush mechanisms for rotating brushes or groups of brushes as indicated by U.S. Pat. Nos. 2,215,031, 2,140,317 and 4,156,620. In some cases the tufts of bristles are driven rotatably and in other cases, rotational oscillation of the tufts of bristles is induced. Further, turbine powered, gear train controlled brush mechanisms have also been widely used in powered brushes of types other than toothbrushes as indicated by U.S. Pat. Nos. 4,513,466; and 4,461,052. Powered brushes having water supply to the brush head have also been widely used in toothbrushes and in brushes that have been designed for other purposes.
Where powered toothbrushes are employed which incorporate gear mechanisms for inducing tooth cleaning motion for tufts of bristles, the brush head typically incorporates a number of small gears. Because dentifrice typically contains abrasive particulate and since food debris is removed from the teeth and other portions of the oral cavity during tooth cleaning and becomes entrained in the dentifrice/water/oral fluid composition, the small gears of the brush head often become fouled and stall or stop functioning completely such that disassembly and cleaning or replacement of the brush drive mechanisms becomes necessary. It is desirable, therefore, to provide a system for effectively preventing fouling of the gears during toothbrushing activities and insuring that upon completion of tooth cleaning activities it will not be necessary to spend additional time and effort in cleaning the toothbrush mechanism itself. Even under circumstances where the brush head gearing is sealed and gear fouling is not a problem it may be desirable to provide for discharge of water from the brush head into the oral cavity of the user or for other desired purposes.